Sizzling heat is not shown in the chart at left. The metal stiffens as it cools down and cannot be worked as easily when it cools to lower temperatures. A good rule of thumb for most shaping of mild steel and wrought iron is to work it when heated yellow, and put it back in the fire when it cools to red.
UIO redirects here. For other uses, see UIO (disambiguation). Mariscal Sucre International Airport (Spanish: Aeropuerto Internacional Mariscal Sucre) (IATA: UIO, ICAO: SEQM) is the busiest airport in Ecuador and one of the busiest airports in South America.
Quitoâs International Airport. Quito is also home to the newest international airport in Latin America: Quitoâs Mariscal Sucre Airport (UIO) about an hour to the east of the city. Hotels and Lodging in Quito. There are myriad Quito hotels and hostels of all types and price levels.